Amorphous optical coatings of present gravitational-wave interferometers

  title={Amorphous optical coatings of present gravitational-wave interferometers},
  author={Massimo Granata and A. Amato and Laurent Balzarini and Marco Canepa and J{\'e}r{\^o}me Degallaix and D. Forest and Vincent Dolique and Lorenzo Mereni and C. Michel and L. Pinard and Beno{\^i}t Sassolas and Julien Teillon and Gianpietro Cagnoli},
  journal={Classical and Quantum Gravity},
We report on the results of an extensive campaign of optical and mechanical characterization of the ion-beam sputtered oxide layers (Ta2O5, TiO2, Ta2O5–TiO2, SiO2) within the high-reflection coatings of the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors: refractive index, thickness, optical absorption, composition, density, internal friction and elastic constants have been measured; the impact of deposition rate and post-deposition annealing on coating internal friction… 

Structure and morphology of low mechanical loss TiO2-doped Ta2O5

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Demonstration of the Multimaterial Coating Concept to Reduce Thermal Noise in Gravitational-Wave Detectors.

Experimental verification of the multimaterial concept is presented, by integrating aSi into a highly reflective SiO_{2} and TaO_{5} multilayer coating and showing a significant thermal noise improvement and consistent optical and mechanical performance.

In-vacuum measurements of optical scatter versus annealing temperature for amorphous Ta2O5 and TiO2:Ta2O5 thin films.

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The correlation highlights that both the electronic states responsible of Urbach tail and the internal friction are sensitive to a self-correlation of defects on a medium-range scale, which is promoted by annealing and in this case, to a lesser extent, by doping.

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The genomics approach to materials, heralded by increasingly accurate density functional theory (DFT) calculations conducted on thousands of crystalline compounds, has led to accelerated material

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On April 1st, 2019, the Advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO), joined by the Advanced Virgo detector, began the third observing run, a year-long dedicated search for

Thermal noise study of a radiation pressure noise limited optical cavity with fused silica mirror suspensions

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Internal Friction and Urbach Energy Correlation

The understanding of how the structure rules the several properties that distinguish amorphous solids from crystals is important for a technological progress, regarding several applications. The



Thermal noise in interferometric gravitational wave detectors due to dielectric optical coatings

We report on thermal noise from the internal friction of dielectric coatings made from alternating layers of Ta2O5 and SiO2 deposited on fused silica substrates. We present calculations of the

Effect of elevated substrate temperature deposition on the mechanical losses in tantala thin film coatings

Brownian thermal noise in dielectric multilayer coatings limits the sensitivity of current and future interferometric gravitational wave detectors. In this work we explore the possibility of

Mechanical loss in state-of-the-art amorphous optical coatings

We present the results of mechanical characterizations of many different high-quality optical coatings made of ion-beam-sputtered titania-doped tantala and silica, developed originally for

A study of coating mechanical and optical losses in view of reducing mirror thermal noise in gravitational wave detectors

Mirror coatings play a crucial role in the performance of laser interferometers devoted to gravitational wave detection such as Virgo and LIGO. Mechanical losses in the coating material limit the

Mechanical loss in tantala/silica dielectric mirror coatings

Current interferometric gravitational wave detectors use test masses with mirror coatings formed from multiple layers of dielectric materials, most commonly alternating layers of SiO2 (silica) and

Effect of heat treatment on mechanical dissipation in Ta2O5 coatings

Thermal noise arising from mechanical dissipation in dielectric reflective coatings is expected to critically limit the sensitivity of precision measurement systems such as high-resolution optical

Progress in the measurement and reduction of thermal noise in optical coatings for gravitational-wave detectors.

This review, after a brief overview of the techniques for coating thermal noise measurements, presents the latest worldwide research activity on low-noise coatings, with a focus on the results obtained at the Laboratoire des Matériaux Avancés.

Mechanical and thermoelastic characteristics of optical thin films deposited by dual ion beam sputtering.

This work systematically study the growth and the mechanical and thermoelastic characteristics of niobium oxide, tantalum oxide, and silicon dioxide thin films prepared by dual ion beam sputtering to investigate the stress, hardness, reduced Young's modulus, and scratch resistance.